Photosynthesis and plant cells

Question 1

What are stomata?

Answer 1

Stomata are tiny holes in epidermis who control water loss/ exchange of gases

Question 2

If a plant is in a desert environment, will the guard cells be open or closed?

Answer 2

They would be closed so that the water can be kept in the plant.

Question 3

How do you differ from a plant cell and a root hair cell?

Answer 3

• Root hair cell has root hair.

- Root hair has no chloroplasts.

Question 4

What is the function of the xylem?

Answer 4

• Transports water in the plant.

- Supports the plant.

Question 5

Why does the xylem have no cytoplasm and no end walls?

Answer 5

So it forms a continuous tube that can carry the water

Question 6

What is the xylem strengthened by in the cell wall?

Answer 6

It is strengthened by lignin, which is a tough, waterproof substance.

Question 7

In plants, what are leaves examples of?

Answer 7

Leaves are examples of organs.

Question 8

What is the function and adaptation of a leaf cell?

Answer 8

Leaf cells absorb sunlight for photosynthesis.

• Large surface area.
• Lots of chloroplasts.

Question 9

What does the phloem in plants do?

Answer 9

The phloem transports food in a plant.

Question 10

What do plant epidermal cells do?

Answer 10

Plant epidermal cells create a protective layer to ensure that no water is lost. Can be at the lower epidermis or upper epidermis.

Question 11

What are epithelial cells?

Answer 11

Epithelial cells are cells on the lining of an organ.

Question 12

What is the function of the permanent vacuole in plant cells?

Answer 12

In plant cells, the permanent vacuole contains cell sap which keeps it turgid.

Question 13

What is the function of the nucleus?

Answer 13

• Controls any activity in the cell.

- Contains genetic information.

Question 14

What is the function of the mitochondria?

Answer 14

Mitochondria is where energy is released, where aerobic respiration takes place.

Question 15

Where is cellulose found and what is it’s function?

Answer 15

• Cellulose is found in the cell wall of plants.

- Helps for it to remain stiff and strong.

Question 16

Why is the cell membrane in a root hair cell elongated?

Answer 16

The cell membrane is elongated to maximise the amount of water it absorbs.

Question 17

Why are there a lot of mitochondria in a root hair cell?

Answer 17

The mitochondria releases energy, needed to absorb minerals by active transport.

Question 18

How is water absorbed by a plant?

Answer 18

It is absorbed by osmosis. This is when water moves from an area of high concentration to an area of low concentration, down a concentration gradient.

Question 19

How are root cells adapted specifically to absorb water?

Answer 19

• Thin cell membrane: Makes a short diffusion distance.

- Long cell membrane: Increases the surface area for diffusion.

Question 20

What is active transport and what does it require?

Answer 20

Active transport is the process required to move molecules against a concentration gradient. From an area of low concentration to high concentration. This requires energy.

Question 21

What is passive transport?

Answer 21

Transport as a result of movement of random particles, there is a net movement from high concentration to low concentration.

Question 22

Why does a large surface area increase diffusion?

Answer 22

When a cell’s surface area increases, the amount of substances diffusing into the cell increases.

Question 23

What is photosynthesis?

Answer 23

Photosynthesis is an endothermic chemical reaction used by plants. It makes glucose + oxygen from carbon dioxide+ water.

Question 24

What is an inorganic substance?

Answer 24

An inorganic substance is a compound that does not include carbon bonded with hydrogen.

Question 25

How is the palisade mesophyll adapted for photosynthesis?

Answer 25

• Packed with many chloroplasts.
• They are column shaped (increases the surface area and takes in more carbon dioxide) and arranged closely together.
• Towards the upper surface of the leaf.

Question 26

What does the waxy cuticle at the top of the leaf cell do?

Answer 26

The waxy cuticle prevents water loss.
It is waterproof.
The wax is produced by the epidermal cells.

Question 27

What do the epidermal cells do?

Answer 27

• They produce wax which ensures that there is no water loss.
• The upper epidermis is transparent so the light can pass into the palisade layer.

Question 28

Why do the spongy mesophyll cells have a lot of air spaces?

Answer 28

Spongy mesophyll cells have a lot of air spaces to allow carbon dioxide to reach the palisade cells.

Question 29

Where are the xylem and phloem tubes found in a leaf cell?

Answer 29

• The xylem and phloem tubes are found in the spongy mesophyll layer.
• They transport water and nutrients in the plant.

Question 30

What four things are needed for photosynthesis to occur?

Answer 30

• Light.
• Carbon dioxide.
• Water.
• Chlorophyll.

Question 31

When oxygen is released in photosynthesis, how does a plant use it?

Answer 31

• Plants use oxygen for respiration.

- It is also available for animals and micro-organisms that need to respire.

Question 32

What is biosynthesis?

Answer 32

The production of more complex molecules from simpler ones in organisms.

Question 33

What do plants use glucose for?

Answer 33

• Respiration.
• Fat/ oil produced, used as storage in seeds.
• Cellulose strengthens the cell wall.
• Used to produce amino acids with nitrate ions in the soil.
• Converted into insoluble storage starch.

Question 34

How do you test for oxygen to see if photosynthesis has been carried out in a plant?

Answer 34

• Place a plant in a beaker with water.

- If it gives off bubbles, oxygen is present.

Question 35

How can you test the presence of sugars? Give a step-to-step process.

Answer 35

1.) Grind up the food sample with a pestle and mortar.
2.) Add to test-tube with Benedict’s solution.
3.) Heat up the solution in water bath.
If it turns red from blue then it has sugar in it.
If no sugar, there will be no change.
If there is a little bit of sugar it will turn green - orange.

Question 36

What process do plants do at night?

Answer 36

• Plants respire at night.

- They cannot respire because there is no light.